Thanks, watching (read hearing) this just saved me stripping engine down as I was convinced that knocking was mechanical and couldn't possibly be that bad just from out of balance carbs....now where did I put that carbtune...
I had exactly the same problem. I cured it by overhauling the carbs using Keyster refurb kits. I bought four for £48 from the US. They are a lot more if bought in the UK. Of course, once you've messed around with the innards, it's best to synchronise the carbs. I bought the Morgan Carbtune directly from the manufacturer cheaper than ones on eBay! Failing that, just replace the needle valves.
i still have my from new 1974 cb400f and I did the carbs static and they run sweet tick over at 1200 revs still orginal pipe quite just here the cam chain rattle .
Thanks, watching (read hearing) this just saved me stripping engine down as I was convinced that knocking was mechanical and couldn't possibly be that bad just from out of balance carbs....now where did I put that carbtune...
Yes! I just did my cb400f cafe and o boy were they off BIG TIME! My bike runs so smooth sounds almost like a 600rr with the pipe I have on it too..
I had exactly the same problem. I cured it by overhauling the carbs using Keyster refurb kits. I bought four for £48 from the US. They are a lot more if bought in the UK. Of course, once you've messed around with the innards, it's best to synchronise the carbs. I bought the Morgan Carbtune directly from the manufacturer cheaper than ones on eBay! Failing that, just replace the needle valves.
i still have my from new 1974 cb400f and I did the carbs static and they run sweet tick over at 1200 revs still orginal pipe quite just here the cam chain rattle .
Man, I gotta get me a CarbTune unit :D
Probably bad floaters or gummed up jet from what I've seen. Better get your carbs properly cleaned.
Valves need adjustments